Download SLIPPED FEMORAL EPIPHYSIS Incidence: 2/100000 Mean age

SLIPPED FEMORAL EPIPHYSIS Incidence: 2/100000 Mean age: Males 13 and Females 11 years Male predominance Bilateral in 25% Polynesian: 4.5 times Caucasians Autosomal dominance with incomplete penetrance 7% if sibling affected and 3% with parent affected Obesity seems to be a key factor increase shear stress at the physis Pathogenesis Mechanical when obesity is associated with: a. Reduction in anteversion of the femoral neck b. Abnormal slope of the growth plate Increased physeal height The thinning of the perichondral complex Maturation factors The slip appears to occur in a narrow skeletal age range. In girls SCFE almost exclusively occurs before the menarche. Endocrine High growth hormone and low testosterone Routine testing for hormones is controversial In endocrinopathy are usually bilateral at first presentation Signs and symptoms In over 50% of cases there is a history of injury. Pain is in the groin but very often around the knee between 10‐15 years. Antalgic gait is present. Some patients can not weight bear. Typical history of gradual onset over few weeks. Deformity: Adduction and External rotation of the Hip Movement of the hip: Limitation of Flexion, Internal Rotation and Abduction. Shortening of 1‐2 cm is common RADIOLOGICAL EXAMINATION AP, True lateral, Frog leg 1.Klein’s line: Line along the superior border of the neck, normally cuts the epiphysis Trethovan’s sign: Klein’s normally cuts the physis 2. Capeners sign The medial junction of Epiphyseo‐metaphyses is outside the acetabulum 3.Metaphyseal blanch sign of Steel. – Posterior lip of the epiphysis as it begins to slip posteriorly producing a superimposed shadow on the neck Look for Remodeling, AVN, Chondrolysis 3
1 2 Classification Mild Moderate Severe LOADER Classification Stable Unstable Weight bearing Possible Not possible Severity of slip Less severe More severe Good prognosis 96% 47% AVN 0% 50% TREATMENT Commonly used treatment: Is in situ pinning using one central screw. 93% good result. Up to 60% displacement can remodel. Can allow Touch to partial weight bear for 6 wks Ideally single screw is used. As complication increases with number of screw used: 1 pin 5% complication, 2 pin 20%; 3 pin 30% [Blanco] Present recommendation is equal distribution of threads across the physis when using 16‐mm thread screws with minimum 3‐4 threads in the physes. This treatment is adequate for Mild and moderate slip. In severe slip, the initial treatment is in situ screw fixation. Forceful reduction should be avoided as this causes avascular necrosis. Usually patient will have deformity which may remodel or can be treated at later date `with subtrochanteric osteotomy [Southwick osteotomy] a year or two later. Subtrochaneric osteotomy .
Complications 1. Avascular necrosis [AVN] Causes Forceful reduction is the important cause for AVN. Neck osteotomies to reduce SFE is associated with high risk of AVN Multiple screws: Complication rate increases by 10‐fold with each increase Incidence In situ pinning In unstable Slip Neck osteotomy 5% 50% 15% Treatment options Leave them alone Valgus osteotomy Arthrodesis Later THR 2.Chondrolysis Causes: Immobilisation, Pin penetration which was not unrecognised, proximal femoral osteotomies, increased severity of slip. Clinically present with a pain, stiffness. X ray reduced joint space <3mm in bilateral 5 % incidence Rx: Antiinflammatory, CPM, Traction 50% will resolve 3.Osteoarthritis In a large series of Osteoarthriitis hips, SFE accounted for 5% Untreated SUFE Type III, will be symptomatic within 15 years At 40 yrs: all slipped epiphyses end up with moderate to severe osteoarthritis. 4. Coxa vara and shortening: May lead to secondary osteoarthritis